Inner tube



Apr. 10, 1923.

, M. P. MITCHELL INNER TUBE Filed Mar. 25, 1920 04, I di SMQ,

Patented Apr. 10, 1923.

MARY PIERSON MITCHELL,A OF EATON, OHIO.

PATENT OFFICE.

INNER TUBE.

Application led March 25, 1920. Serial No. 368,590.

To l u1/10m. it may concern Be it known that I, MARY IIEnsoN MlToH- nm.,a citizen of' the United States, residing at Eaton, in the county oflreble and State ot' Ohio. have invented a new and useful Inner Tube,of' which the following is a specification.

to improve generally and to enhan'ce thev utility7 of devices ofthattype to which the invention appertains. I

ll'ith the above and other. objects in view, which will appear as thedescription proceeds` the invention resides in the combination andarrangement of parts and in the details of construction hereinafterdescribed and claimed, it being understood that, within the scope ofwhat is claimed, changes in the precise embodiment of lthe inventionshown can be made without departing from the spirit of the invention.

In the accompanying drawings:

Figure l shows in transverse section, an

inner tube equipped with the reinforcement,

forming the subject matter of this application: Figure 2 is a detailenlarged from Figure 1; Figure 3 is a plan of the reinforcement, thesame being laid fiat; and Figure 4 is a diagrammatic cross sectionshowing a modified form of the invention.

In carrying outl the present invention, there is provided areinforcement including a piece of netting denoted by the numeral 1..\lthough any desired material may be used in the making of the netting,wire is pre- 'l'erred. and any kind of metal having the necessarycharacteristics. such as flexibility, resiliency or strength may beemployed. 'l`he netting preferably but not necessarily is cleaned in`any desired way'. such as by the application o'f benzine, gasoline,naphtha or the like. although` in practice. it may be found possible toclean the netting mechanically. The cleaning step may be dispensed with,sometimes. but when the best possible results are desired, the cleaningstep is resorted to.

After the wire netting 1 has been cleaned, if it is considered desirableto clean the netting, cords 2 may or may not be incorporated in thenetting. The cordsmay bemade of cotton. linen or any other suitablesubstance, and are incorporated with the netting by threading themthrough the netting or by weaving them into the netting along -With thewires of the netting. It is to be understood distinctly that the cords2` may be omitted if desired, but when they are used, they aid -inholding the rubber on the netting, as will be explained'hereinafter.

The netting l and the cord 2, if the. cords are used, are treated witha. vulcanizable cement. The cement may be worked into the meshes of thenetting by means of a brush or swab, or by hand, or the netting may bedipped into the cement. It may bey desirable to dip the netting into thecement repeatedly. After the netting has been treated .with cement, thecement is dried partially or is permitted to dry. l

This drying operation may be carried out in any desired way. In someinstances, the netting is merely hung up and permitted to dry until thecement is tacky enough to' exercise its function Without running ordripping. The netting is incorporated with one or more layers of rubberin any desired way. In `some instances, the netting, covered with thepartially dried cement, is rolled into or upon the layer of rubber andthe rubber may be coated with cement if desired. Again, as shown in thedrawings,

the netting is placed between layers 3 of rubber, before thevulcanizable cement has dried completely, the rubber then beingvulcanized, to form, vwith the netting, aI unitary reinforcement.

The reinforcement, constructed as set` forth, is introduced into thetread portion of an inner tube 5, or is placed otherwise therein, ashereinafter explained. As indicated at 6, the reinforcement, in one formof the invention, does not extend entirely around the tube 5,transversely, one half of the tube, more or less, considered trans'-versely being devoid of the reinforcement. In any event, however, thetread portion of the tube is reinforced throughout such an area as islikely to be subjected to puncture. The reinforcement is iexible enoughso that it will not interfere materially with ment v is placed inte welladapted to withstand the bending of the tube and since the reinforcementdoes not extend entirely around the tube, transversely the tube,obviously may expand. The reinforcement extends throughout the M of thetube considered circumferentially. Y

As depicted in F 4L, one reinforcetread of the tube l1, anotherreinforcement 12 being placed in the inner portion of the tube. Thereinforce'ments are spaced apart, along their longitudinal edges,ciently so that the tube may expand.

Refractory material, such as soa-pstone, or asbestos is applied to theouter surface of the tube in any desired way. According to one method ofprocedure, the outer surface of the tube may be covered thinly Ywithcement and upon this cement, the asbestos 4 is placed. In allu toasbestos, it'is to be understood that an impalpable powder is notemployed, the asbestos being the commercial bulk powdered asbestos whichfalls far short ot being an impalpable powder. Asbestos need not beused, but if it is employed, it serves to prevent the tube from hea,when the tube. frictional contact. with ect to the tlre casing.

It will be obvious that an inner tub-e for tires, constructed as aboveset forth, will be pinching, and will be strehened and reinforced. Itis'well own that, if the inside of a tire casing is cracked slightly, orif the fabric fails, to a slight extent, not enough to produce ablowout, the inner tube, nevertheless, is we pinched and, after a shortperiod -u tears or puncpuneture and v Merece tures. Since the tubeforming the subject matter of this application isrreinforced, the tubewill not enter readily into small fissures in the inner surface o thecasing and be- I come pinched or damaged as aforesaid.'

Having thus described the invention, what l claim as new and desire toprotect by Letters Patent of the United States is I-f 1. An inner tubefor'vehicle tires, em-

`bodying a layer of yWire netting coated with 3. An inner tube foryvehicle tires em-.

bodying layers of material which are treated with vulcanizable cement;and .9.a layer of wire netting located between the aforesaid layers, thelayer of wire netting being coated with adhesive material VVWhich isdried to a point of tacky adhesion. prior to the assembly of the-tube.

4. An inner tube for vehicle tires, em!

bodying a netting composed in part of '-lnetal and in part of cords, thenetting being coated withadhesive material which is dried to a point oftacky adhesion prior to the assembly oithe tube.

In testimony that I claim the foregoing as my own, l have hereto affixedmy signature in the presence of two witnesses.

nv PiERsoN MITCHELL.

Witnesses: i

CLIFFORD H. STROH, R. A. SAYLOR.

